In Situ Transmission Electron Microscopy for Energy Storage Materials and Beyond

In situ transmission electron microscopy (TEM) enables us to "see" dynamic processes of atomic scale phenomena in real time. For example, it is now possible to observe the change in the atomic structure of the Li-ion battery electrode materials during the charge/discharge cycles. A single nanowire battery was created inside TEM in the experiment, and the change in the morphology was recorded as the nanowire reacted with Li ions. Various materials were tested and their response to the Li insertion was compared. The observation provides rich information of the reaction mechanism and possible solutions to improve the device performance.

Li-ion battery is a widely commercialized energy storage technology, but nano-engineered electrodes are demonstrated to further improve the function such as, capacity, cycle-lifetime, and rate performance. Here, insights obtained from in situ TEM experiments can be directly linked to their performance and contribute to developing novel electrode materials. In-situ TEM technique to evaluate the mechanical properties in nano-scale was also developed and applied to evaluate the stability of the nano-structured electrode materials. The technique can potentially be applied beyond the battery materials, and it is being further developed to characterize more complex phenomena such as tribology and fatigue.

Nanotechnology is an inextricable part of our modern everyday life, and nano-characterization technique such as in situ TEM is a powerful tool to understand the materials from atomic scales and contribute to advancement of the technology. Atoms are small, but observing, understanding, and utilizing their behavior may lead to technological breakthroughs making huge impacts on our society.

Biography

Dr. Akihiro Kushima is a Research Scientist in the Department of Nuclear Science and Engineering at Massachusetts Institute of Technology (MIT). His research interest is to understand the fundamental materials properties through combination of in situ electron microscopy and atomistic simulations with particular emphasis on energy storage materials. Dr. Kushima completed his Ph.D. and undergraduate studies in the Department of Engineering Physics and Mechanics at Kyoto University, Japan in 2007. Prior to his current position, he conducted postdoctoral studies at MIT (2007-2010) and University of Pennsylvania (2010-2012). He started his research career as a theorist in the field of computational materials science specialized in ab initio quantum mechanics simulations. During his appointment at University of Pennsylvania, he studied in situ transmission electron microscopy (TEM) technique at Center of Integrated Nanotechnologies at Sandia National Laboratories to understand the atomic scale reaction mechanism of Li-ion battery electrode materials under the battery operation. As a Research Scientist at MIT, he is currently developing in-situ TEM techniques to observe complex deformation process in nano-scale (tension, tribology, fatigue, etc.), and liquid-confining cell for observing solid/liquid interface reaction inside TEM. His research areas include Li-ion/air battery, nano-materials, solid-liquid interfacial reaction, and developing in situ TEM techniques.